Grains and field crops, Natural resources
The residual value of Christmas Island C-grade ore, 500 degrees C heated (calcined) C-grade ore (Calciphos), and superphosphate was measured in three experiments. Plant yield, and bicarbonate-soluble phosphorus extracted from the top 10 cm of soil were used to indicate the effectiveness of the four fertilizers. Using either of these indicators, superphosphate was the most effective fertilizer.
Number of Pages
Rock phosphate, Superphosphates, Phosphorus fertilizers
Bowden, J W, and Bolland, M D. (1987), Residual value of rock phosphate fertilizers. Department of Agriculture and Food, Western Australia, Perth. Technical Bulletin 75.